gl: Add a back pointer from the window to the context

This way we can check if a GdkWindow has a GdkGLContext associated to
it.

2 files changed, 33 insertions, 2 deletions

diff --git a/gdk/gdkglcontext.c b/gdk/gdkglcontext.c
index f5e543c6a4..528bd26779 100644
--- a/gdk/gdkglcontext.c
+++ b/gdk/gdkglcontext.c
@@ -38,6 +38,7 @@
 #include "gdkdisplayprivate.h"
 #include "gdkglpixelformat.h"
 #include "gdkvisual.h"
+#include "gdkinternals.h"
 
 #include "gdkintl.h"
 
@@ -393,15 +394,21 @@ gdk_gl_context_set_window (GdkGLContext *context,
   GdkGLContextPrivate *priv = gdk_gl_context_get_instance_private (context);
 
   g_return_if_fail (GDK_IS_GL_CONTEXT (context));
-  g_return_if_fail (window == NULL || GDK_IS_WINDOW (window));
+  g_return_if_fail (window == NULL || (GDK_IS_WINDOW (window) && !GDK_WINDOW_DESTROYED (window)));
 
   if (priv->window == window)
     return;
 
+  if (priv->window != NULL)
+    gdk_window_set_gl_context (priv->window, NULL);
+
   g_clear_object (&priv->window);
 
   if (window != NULL)
-    priv->window = g_object_ref (window);
+    {
+      priv->window = g_object_ref (window);
+      gdk_window_set_gl_context (window, context);
+    }
 
   GDK_GL_CONTEXT_GET_CLASS (context)->set_window (context, window);
 }
@@ -490,3 +497,22 @@ gdk_gl_context_get_swap_interval (GdkGLContext *context)
 
   return priv->swap_interval;
 }
+
+gboolean
+gdk_window_has_gl_context (GdkWindow *window)
+{
+  return g_object_get_data (G_OBJECT (window), "-gdk-gl-context") != NULL;
+}
+
+void
+gdk_window_set_gl_context (GdkWindow    *window,
+                           GdkGLContext *context)
+{
+  g_object_set_data (G_OBJECT (window), "-gdk-gl-context", context);
+}
+
+GdkGLContext *
+gdk_window_get_gl_context (GdkWindow *window)
+{
+  return g_object_get_data (G_OBJECT (window), "-gdk-gl-context");
+}
diff --git a/gdk/gdkinternals.h b/gdk/gdkinternals.h
index 791fa87b22..9dfd9b544c 100644
--- a/gdk/gdkinternals.h
+++ b/gdk/gdkinternals.h
@@ -407,6 +407,11 @@ void _gdk_synthesize_crossing_events_for_geometry_change (GdkWindow *changed_win
 gboolean    _gdk_window_has_impl (GdkWindow *window);
 GdkWindow * _gdk_window_get_impl_window (GdkWindow *window);
 
+gboolean        gdk_window_has_gl_context       (GdkWindow    *window);
+void            gdk_window_set_gl_context       (GdkWindow    *window,
+                                                 GdkGLContext *context);
+GdkGLContext *  gdk_window_get_gl_context       (GdkWindow    *window);
+
 /*****************************
  * offscreen window routines *
  *****************************/